Page 188 - IJB-9-3

International Journal of Bioprinting Chitin/gelatin/PVA scaffolds

Figure 3. Load-deformation curves for 3DP inks. Figure 4. Textural profile analysis (TPA) of 3DP inks.

Figure 5. Optical images of (A) the hybrid scaffold macrostructure (scale bar = 4 mm) and (B) the nanofibrous mat on the pore of the 3D-printed scaffold
(scale bar = 200 µm).
material before breaking and it indicates the strength of the With the aim of assessing the potential of these
internal bonds of the material . Since cohesiveness is the multilayered scaffolds for tissue regeneration, such as
[59]
ratio between the areas of the second and the first cycles, wound healing, biocompatibility was determined using
the value close to 1 suggested that the material recovered human dermal fibroblasts. The short-term biocompatibility
the shape. (Figure 6) was evaluated based on the metabolic activity
and cell mortality along 72 h. Regarding the activity, cells
3.4. Characterization of 3DP-ES scaffolds had optimal activity values from the first date (75.0%),
The shape fidelity and dimensional stability of the scaffold showing an ascending trend with the course of the days
is shown in Figure 5A, where an image of a 3DP-ES scaffold, (91.8% at 48 h and 106.8% at 72 h). Additionally, the cell
obtained by optical microscopy, can be seen. Additionally, mortality was maintained around 10% along the studied
the electrospun mat attached to the 3D-printed layer can time points (10.3, 7.6, and 8.4% at 24, 48 and 72 h,
be observed in Figure 5B. The resulting scaffolds showed respectively).
an average porosity of 2.5 mm in the 3D-printed layer
and an average value of 64 µm in the electrospun layer. Concerning long-term biocompatibility assay,
This porosity can allow the cells to seed without falling to the cells observed with the live/dead fluorescence kit
the bottom of the culture plate so as to ensure 3D spatial showed optimal results (Figure 7). From 1 to 7 days of
deposition [15,22] . Since the combination of electrospun culture, the vast majority of the cells were alive, although
nanofibers with larger structures resulted in complex some mortality labeling was observed. This tendency,
hierarchical scaffolds that can mimic the highly organized although non-significant, could have been due to the
structure of tissues and improve biological performance, high confluence of the culture. Likewise, the cells showed
biocompatibility tests were carried out. Results showed that a normal fibroblastic phenotype, with spindle-shaped,
this structure ensures the desired interconnected porous central and elliptical nucleus and long cytoplasmic
architecture to achieve successful growth of cell culture. prolongations.

Volume 9 Issue 3 (2023) 180 https://doi.org/10.18063/ijb.701